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13rendan_88
12th February 2008, 08:37 PM
i have been trying to decide for months now what to do with my ae71 and i was very keen on 4age, but today dad was telling me he recommends twin carbies on the engine i got now which is a 4ac and also totally rebuild it. has anyone done this? dad had twin carbies on his holden gemini when he was younger and he said it was excellent. screamed and was fast. i know that means also needing a custom manifold?

so yeh the question is how many people out there have fully worked a 4ac and also put twin carbies on it? and if so how much does it put out?

thanks
Brendan

Course_Out
12th February 2008, 09:06 PM
Go to http://www.club4ac.com/ - there is a guy on there from Hawaii that is using a 4ac on twin carbs. From memory he has a ridiculously rare HKS twin sidedraught manifold.

At the end of the day though the 4ac is a non cross flow head so it's never going to flow as well as a 4age. I have heard guys in America getting close to the 100kw mark at the flywheel but your looking at a pretty grumpy, heavily worked motor that will just keep up with a stock 4age (maybe, I would doubt it would even manage that due to the torque deficit it would more than likely have)

Also you will find that unlike the g series motors in the old Gemini's no one over here has really spent time/money on a 4ac. Dave (Truenosedan on here) turbo charged one but it was a bit rough and a bit of a hand grenade (no disrespect to Dave, I'm paraphrasing his own words here)

If you wanted to go completely silly with it you could always use a 7afe bottom end for a 1.8 litre engine but I don't think it's been done before. Another option is to use a 4afc head/carb - that is a narrow angle twin cam head so you would pick up a few kw - also you could probably pick up a whole car containing a 4af (ae92 Corolla from memory) for the price of a 4age and have the rest of the car to wreck and sell...

I personally am going twin carbed 4age - manifolds are available off the shelf and it has been reasonably popular over the years - I won't revisit the ins and outs here, a quick search will answer any questions you have.

Sorry this was so long winded, I just wanted to get in before 50 people posted saying "sif do up 4ac, " etc etc

4A-GE Power
12th February 2008, 09:40 PM
4AGE anyday of the week bud. The 4AC is a great motor, just doesn't make much power even when worked, so there is not much point apart from the novelty. And you can pick up a 16v pretty cheap, so its a bit of a no-brainer!

Course_Out
12th February 2008, 09:42 PM
http://www.club4ac.com/index.php?showtopic=402

RobertoX
12th February 2008, 09:45 PM
do it, it will teach you lots of things

if it doesnt go, chuck nos on it, blow up ten and have fun!~

Gunner
12th February 2008, 09:59 PM
^^^thats the way

riojin
12th February 2008, 10:00 PM
NOS ftw

http://www.fakejazz.com/images/nos.jpg

Gunner
12th February 2008, 10:14 PM
the best fun i ever had was in my little single cam tx3, was injected tho, shaved, ported, and the lumpiest cam u can find lol, and then gas to go bang lol i love gas mmmmm